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Larry Richwine
Director of Technical Services
6705 E 900 N, Brownsburg, IN 46112
PH 317-852-0630 
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To order a NTPA rulebook, order online, call the NTPA office at 614-436-1761 or mail $6 plus $2 shipping and handling to WPI/NTPA, 6155-B Huntley Rd. Columbus, OH 43229.


Update: After consideration the rule has been changed to exempt the Heavy Pro Stock Class.

The following rule goes into effect Aug 10, 2022:

New rule added to the 2022 NTPA rulebook (general rules) pg 27 letter G under engines, a new #7 which reads:

Diesel fuel injection lines must be a minimum of 24 inches in length from the injection pump to the injector. This applies to all classes with a diesel engine.

Note: The Heavy Pro Stock class, V-8 engines and high pressure common rail systems including electronic fuel injection are exempt of this rule.


V and Y type engine side shield Rule update:

The new rule as stated below will remain a recommendation for 2022. Previous engine side shield rule will be honored for the 2022 season.

The rule listed in the 2022 NTPA rulebook on page 29 #5 that reads:

5. Shielding on all V and Y type engines (including marine and aircraft)

a. Side shield must extend from base of head or the uppermost part of the piston and travel to 2” below bottom center of crankshaft throw, and be securely fastened.

b. Side shield must be made from minimum .060” steel or aluminum and positioned within 3 inches of block.

c. Shield must cover full length of block and extend from bottom of cylinder head to 2 inches below bottom center throw of crankshaft.

d. Shield must be bent 90 degrees at bottom and extend horizontally inward to meet engine oil pan.

Note this is only a recommendation for 2022

Attention pullers using Bio-diesel:

When ordering Bio-diesel from MEG Corp, you need to order “B60” it is formulated as NTPA legal. The “B80” formula is not NTPA legal. They are both B100 with different additive for wet stacking. 

Please take note as it is your responsibility to be legal.

Click here to view the B100 Bio fuel test standard and the conversion chart

NTPA Rule Update: Effective immediately (this includes Shipshewana):

Page 28 of the 2022 NTPA rulebook “Shielding” #1 letter now reads:

J. All inline turbocharged engines are required to have a cable(s) placed between first and second cylinder through exhaust manifold port area. Cable must be a minimum of one (1) 3/8 manufactured pendant line with a rating of at least 3000 lb or more with a tag from the manufacture that indicates rated load capacity with swaged sockets.
Two (2) 3/8" cables with a minimum of 4 clamps at the splice or crimps with a coupler on each cable. Cable(s) must circle the entire head /block assembly with a maximum of 4" slack.

 Example of the pendant line and tag:

IMG 2010IMG 2011


New NTPA Rules for 2022:


Modifieds, Minis, and Trucks must use SFI approved bellhousing.

  • Bellhousings must be mounted as SFI certified by manufacturer with grade 8 studs or bolts that can be identified as grade 8. No hex socket head bolts.
  • Bellhousing attachment must be by minimum grade 8 - 3/8” diameter bolts or studs and must pass through bellhousing flange and block plate. Fasteners installed into engine block or block adapter must be at a depth of 3/8” (.375”) in steel or ¾”(.750”) in aluminum. All other bolts must sandwich bellhousing and block plate using a grade 8 nut and washer. All block plates and block adapters must be made from billet steel or aluminum.
  • All automotive type engines with SFI bellhousings and clutch must run a full block plate, either a unit commercially available, or fabricated from a minimum 3/16” steel or ¼” aluminum.
  • Any SFI bellhousing manufactured with 4 quadrant bolt holes, either 1/2” or ¾”, located two above crankshaft centerline and two below crankshaft centerline, must install proper size minimum grade 5 bolt through both block plate or block adapter and bellhousing per bellhousing manufacturer SFI certification.
  • SFI 6.2 bellhousing must be mounted with qty. 18 - 3/8” grade 8 bolts or studs identifiable as grade 8. No hex socket head bolts allowed.
  • SFI 6.1 and 6.3 bellhousings must be mounted with qty. 15 – 3/8” grade 8 bolts or studs identifiable as grade 8. Qty of 7 installed above crankshaft centerline and qty. 8 installed below crankshaft centerline. No hex socket head bolts allowed. 
  • All bellhousing liner(s) must be made from steel or titanium. Liner must be flush with bellhousing flange / mounting surface and fastened with qty. 1 - ¼” bolt threaded into liner. No modification or rearward movement of liner away from flywheel to allow for larger flywheel or ring gear. Liner can be notched for starter pocket in SFI 6.1 or 6.3 bellhousings.
  • Starting Jan 1, 2023 all SFI belhousings regardless of material i.e. steel, titanium or aluminum must display a current SFI sticker with a expiration date affixed by the manufacture. The NTPA steel stamp will no longer be acceptable as a replacement for SFI decal after Jan 1, 2023

Mini Rod, Transmission Mounting (with planetary type rear axle only)

  • Grade 8 studs, hardened washers, and nuts required when installed externally into bellhousing. Grade 8 bolts with hardened washer acceptable in applications where fasteners are installed from inside bellhousing and threaded into transmission case.
  • Transmission must be fastened to SFI bellhousing using a minimum 2” total bolt diameter.
  • Total bolt circle calculations by qty. x stud diameter
    • 8 – 3/8” (.375”) = 3”
    • 6 – 3/8” (.375) = 2.250”
    • 5 – 7/16” (.4375) = 2.1875”
    • 4 – ½” (.500) = 2”
  • Total bolt circle requirement by transmission manufacturer
    • SCS and TRB – qty. 8 – 3/8” grade 8 studs
    • Profab – qty. 4 – ½” grade 8 studs
    • B&J / Lenco – qty. 5 – 7/16” grade 8 studs 


  • All helmets must be Snell 2015 or newer

Pull Off

  • Eliminate rules 8 and 9 on pg. 88 related to pulloff per proposed agenda item

Diesel Fuel

  • Dielectric constant reading increased to 150 / 13.4 based on meter used.

Limited Pro Stock

  • Steel billet cylinder head(s) allowed.

Classic Super Stock

  • Classic Super Stock class now a recognized Regional National class.

Limited Light Super Stock

  • Engine
    1. Maximum of 410 cubic inches for single turbo charged diesel engines, intercoolers allowed. This engine combination can run a maximum of (1) 3x4 turbo with MAF enhancements, 0.200 MAF enhancements. No forward facing MAF OR (1) 3.4x4 smooth bore turbo.

    2. Maximum of 470 cubic inches for single turbo charged diesel engines. No intercoolers allowed. (The 478 Hercules engine will be legal to run in its factory combination 0% variance on CID). This engine combination can run a maximum of one (1) 3.4 x 4 smooth bore turbo OR (1) 3x4 turbo with MAF enhancement of 0.200 MAF enhancement. No forward facing MAF.

  • Front Axle Suspension – approved for this class.

Pro Farm

  • Turbocharger – require 3” smooth bore (intake and exhaust) turbo.
  • Rule 5 - 3” intake and exhaust slug option eliminated.
  • Weight changed to 9500 lbs.

Mini Rod

  • Stabilizer Bars: Center of stabilizer bar pad must extend 2” behind tire.

Light Unlimited

  • Two-engine limit removed from class rules.


  • Driveline shields must be made of steel, minimum 5/16” thick, and extend at least 6 inches past centerline of each universal joint. No more than ¼” gap between end of shield and gear box or differential. All front driveshafts to have a 5/16” x 2” wide steel, 360 degree safety loop installed at center of front driveshaft and securely mounted to each frame rail by qty. 2 – 3/8” grade 5 bolts evenly spaced.
  • Engines are required to shield all rotating mass mounted to front of crankshaft 360 degrees from front of engine block to one inch in front of the rotating mass. Shield made from 1/8” steel must be constructed to cover outer circumference of damper and extend no more than 1 inch beyond front of damper. Damper shield must be formed to within 1 inch of circumference. Shield must extend rearward to front engine mount, engine block, or oil pan and have minimum 2” lip bent upward in front of damper.Shield must be independently fastened to engine and or chassis with minimum qty. 4 - 3/8” grade 5 bolts.

Shielding on all V or Y-type engines

  • Side shield must extend from base of head or the uppermost part of the piston and travel to 2” below bottom center of crankshaft throw, and be securely fastened.
  • a. Side shield must be made from minimum .060” steel or aluminum and positioned within 3 inches of block.
    b. Shield must cover full length of block and extend from bottom of cylinder head to 2 inches below bottom center throw of crankshaft.
    c. Shield must be bent 90 degrees at bottom and extend horizontally inward to meet engine oil pan

 Tech Questions and Answers

  • Belhousing question


    Mr. Richwine, I bought a new Trick Titanium belhousing for my Mod FWD. I received it in January 2022. It has a current SFI sticker on it and all legal, but, it only has 13 bolts holes around the flange. It also has the 4 big quadrant holes. Do those holes count to meet the 15 bolts requirement? If not, do I need to drill two holes in it to be legal?  I see the rulebook states either 15 or 18 bolts around it to be SFI legal. Please tell me what to do.


     No, don’t drill any holes in it. If they sold it to you as a SFI certified belhousing with only 13 holes it’s legal. If you modify it by drilling extra holes in it won’t be re-certified when you have to send it to Trick Titanium for re-certification because you have modified it.

     Since the rulebook was printed this has come up a couple of times. The bottom line is NTPA wants you to have a “current SFI certified” belhousing properly installed on your vehicle starting January 1, 2023. If Trick Titanium sold you the can as “SFI certified” then NTPA will not tell you to modify it.



    Super Farm injection pump


    Richwine, what’s this I hear about the Scheid injection pump that I’ve been running in the Super Farm class for the past 5 years may not be legal?

    How the hell can that be true?


    The question was raised at Louisville as to the legality of a “P” pump that wasn’t a P7100 housing in the Super Farm class.

    The 2022 NTPA rulebook pg 62 under SF rules states that the pump must be a “P” pump but, doesn’t specify that it has to be “7100 series”.

    After research, review and consideration the NTPA exe board has decided that this issue should be reviewed in September of 2022 by the SF division and better clarified at that meeting for the 2023 rulebook.

    So, the Scheid pump you’ve been running can continue to run for 2022.

    Crossbolts in turbo exhaust


    Richwine, I was told at Shipshawanna that the rules had changed and I had to have 1/2 “ bolts instead of 3/8” bolts as close to the exhaust wheel as possible, Is that true?


    Yes, the rule changed two years ago. You have to have 2  - 1/2 “ bolts in the horizontal part of the pipe as close to the exhaust wheel as possible.  Also, the turbos that have a cross in the turbo exhaust housing from the manufacture doesn’t count. The exhaust pipe still has to have the cross bolts (1/2”) in the horizontal part of the pipe.

    Bio Diesel


    Mr. Richwine

    Is BioDiesel legal for NTPA competition in 2022?  I see where you raised the dielectric reading to 150 but I thought that would eliminate B100. Is this not true? There seems to be a debate if Bio is legal or not.


    We did raise the dielectric limit to 150 for diesel fuel, but, the rules for BioDiesel did not change. The B100 rules are exactly the same as they have been in the past. So, yes biodiesel is still legal.



    Mr. Richwine, my partner and I are coming to Ocala and run the LLSS class. What all do I have to do to pass inspection? We run about all the different groups here in New England, but, we’ve never ran at a NTPA event.


    The NTPA rules for all classes will apply to all of the classes that are scheduled at Ocala. This includes all safety rules like inner side shields, cross bolts in the turbo exhaust pipes, rollcage and attachment, firesuit and equipment, etc. Better get there early and get checked ASAP.

    Reverse light question


    Larry I’m getting close to ready to loading and headed Fl.  I’ve been hearing people needing a neutral light on back of tractor ???  Is this a new rule?? A neutral light and neutral safety switch??? Not sure how power it with safety switch being ground. If it needed.  Sending memberships in next week  so I don’t have new rule book thanks

    NTPA requires a 2 inch white light on the rear of the vehicle to indicate “reverse” as well as a “neutral” switch to keep it from starting in gear.
    The other group requires amber light for neutral.

    Belhousing bolt question

    Mr. Richwine, I was told I can’t use hex socket head bolts to attach my belhousing to my engine / block plate. Is this true?  Some of the bolt holes are so close to the bell that a normal hex head bolt can’t be used. What the heck should I do?

    I understand that this is a problem on some belhousings, so, in this case, you will be allowed to use a hardened hex socket head bolt as long as all the other fasteners are grade 8 bolts and / or studs.

    New Bellhousing rules


    Hey Richwine, what’s this BS that I’ve gota get my steel Lakewood belhousing inspected by Lakewood and have a sticker on it? You guys stamped it so I didn’t have to worry about the sticker or if it was current.


    Yes, Starting Jan 1, 2023 all SFI belhousings regardless of material i.e. steel, titanium or aluminum must display a current SFI sticker with a expiration date affixed by the manufacture. The NTPA steel stamp will no longer be acceptable as a replacement for SFI decal after Jan 1, 2023.

    Mini Rod question


    Hey Richwine, Did the Mini Rod trans mounting rules change after Bowling Green?


    No, nothing changed yet. The number of bolts may change for 2022 but, we will finish the 2021 season same as in the past.

    Pulloffs at Bowling Green


    Mr. Richwine,


    Will there be pulloffs at BG this year? I've noticed that you havent had pulloffs at any events this season.


    Yes, there will be pulloffs if they go past 350 feet. The NTPA rulebook allows for a max distance of 350' I realize we've exceeded that distance at several events but there's not really enough "runoff" room past 350 here at Bowling Green to allow it. The pullers will be red flagged if they go past 350 and will be required to come back for a pulloff. 

    Turbo Blanket


    Can I run if I don’t have a turbo blanket but have it ordered?
    Also, can I build a steel shield around my compressor housing instead of buying a blanket?


    No, you are required to have a Kevlar blanket around you “high pressure” or last turbocharger’s compressor housing in a multi turbo setup. 

    Also No, a steel cover instead of a blanket will not contain the fragments as well as a properly installed blanket.

    If you show up at a NTPA event without a blanket you will have to borrow one or just not pull.

    Note: A turbo blanket is only required in classes that allow a turbo inlet larger than 3 inches.

    Turbo measurement


    Mr. Richwine, I’m new to NTPA, how do you guys measure the turbo? I say that the wheel where it sticks thru the housing should be 3” and everybody tells me I wrong it’s the housing.


    Sorry, they're correct and you’re wrong. When NTPA first started measuring the Super Farm class and actually made them tear the turbo down to be measured and sealed  we set the president of measuring the bore of the housing at the face of the wheel like the rules state.

    We measure several different classes now and they’re all measured the same way. We use a slug or a  “Go /No Go” gauge. Sounds like if measured at a NTPA event that your turbo will not pass.

    Light Limited SS


    Mr. Richwine,

    Are the LLSS rules set in stone? What about the WTPA tractors that don't fit the rules you published? Are you gona allow front suspension?


    The rules that are posted are final and in place for 2021. I suggest that any changes you or any group wish to make be subbmitted for the September meetings of 2021. If they are adopted, they would be in effect for the 2022 season.

    Diesel Fuel rule for 2021


    Hey Mr. Larry,

    Did the NTPA raise their diesel fuel spec like the other guys did?


    No, its still at a max number of 100 for 2021.

    Cables around the engine


    Mr. Richwine, My engine builder wants me to run 3-4 cables around my engine after the Light Pro explosion at a non sanctioned event this summer, can I do that?


    No, only one cable is required or allowed around in line engines in NTPA competition. I understand your engine builders concern but, years ago when the cables were first required we required two cables. We found that only contained the explosion enough to make smaller pieces fly. The cables job is to flip the assembly away from the driver. Everyone always says "but the cable broke" and thats true, but, before it breakes or pulls out of it clamps it does the job as intended.

    If you come to a NTPA event with more than one cable on your engine you will be told to take all the extra ones off before you're allowed to run unless you have a Moline or case, then they require a cable for each head.


    Super Tech


    Richwine are you doing "Super Tech" at Ft Recovery?


    Yes on Saturday from 11am - 2PM on Mini Rods and Unlimited only

    Water test


    Hey Richwine, I hear that the Super Farm pullers had trouble in Rockwell passing the new water test you have. Is that true? what the heck are you doing?


    NTPA does have a new test but, it's no different that PPL's, so if your water will pass there, it will pass here.


    MSD 600 CDI



    Is the MSD 600 CDI unit legal on my mini rod for NTPA competition?


    The Msd 600 cdi by definition of the timing control rule is a legal component when used as only an energy provider for individual coil packs. It only becomes illegal if an external controller is used in conjunction with the 600 cdi in order to adjust ignition timing during a competition run.

    Rain out rules


    Mr. Richwine,

    Please explain how a “Rain Out” works. When can the promoter call it off where I don’t have to show up to get rain points etc. I’ve heard a bunch of different versions of what should or has happened.


    Page 88 of the 2019 NTPA rulebook under letter E Inclement Weather states:

    #7. If a session is cancelled more than 24 hours prior to start time
    at GN/SN or 8 hours at RN/PN/state level, no points will be given
    for that session.
    #8. If a session is cancelled prior to start time, competitors will
    receive refund of paid entry fees, but no other compensation.

    With that said, if the event isn’t canceled within the time period described in #7 then you do have to travel to the event with your pulling vehicle and check in so the entry personnel can record your entry in order to receive rain points. The entry trailer must remain open until scheduled start time of the event in order for you to “check in”.

    As to “Why do I have to take my pulling vehicle with me?” page 81 under Event Procedures and Requirements #4 reads:

    #4. Vehicle must be present on the ground in running order and
    ready to compete before being allowed to enter.

    Light Pro/Limited Pro Stock Turbo



    When the rule says exhaust limit 4.5 inch and the wheel must proturde .125 inch into the bore, will the nut count? Its part of the wheel. Or if I have a couple of little fins in front of the regular wheel will they count? 

    No, the nut doesnt count. The rule says

    1. Turbo limited to 4.5 inch diameter exhaust to be measured at the face of the wheel.
    2. Exhaust wheel tips of wheel (each blade/fin, nut does not count) must protrude into the 4.5 inch bore by 0.125” minimum.
    3. All exhaust must exit the 4.5 inch bore.
      We are going to measure the turbo just like we have on the Super Farm class's 3 inch bore since the days when we "sealed" the turbo with a lead seal.

    If we question how deep it goes into the bore you will be required to disassemble your turbo so we can measure it.

    I included a picture of how / where we will measure the wheel

    turbo exhaust

    Hot Farm tires


    Mr. Larry,
    Can I run my 24.5 tires in the Hot Farm class? I dont want to buy 20.8's but, my tractor fits the hot farm class all but tires.
    If not, WHY not.


    No, you can't run the 24.5 tires in the Hot farm class. The reason is that the class needs to and does look different than all the other classes from the grandstand.
    You will be surprised how good your tractor hooks up with 20.8 tires on it.

    Expired Roll Cage Sticker

    Can I run my tractor with an expired roll cage sticker?
    Yes as long as the old sticker is still in place. The Techs know (becuase they have been told in tech school) that you can run until you find one of the roll cage inspectors.

    Hitch Question


    Mr. Richwine,

    What’s the deal with the new “V” hitch I’ve heard about for Mini rods? Are they legal? Are they gona be allowed in all classes? Asking for a friend.


    No, they aren’t legal the rulebook states in general rules as well as some class rules that nothing can obstruct the chain or the hooking or unhooking of it. The “V” cut design not only would cause difficulty in hooking (if not straight with the sled) but would also make unhooking harder than it already is. Also, when the hook tries to go from side to side when the vehicle gets sideways it will affect the angle of the hook and change the draft of the chain.

    The cross sectional thickness of the point of hook is also spelled out in the rulebook for all classes. This too can affect the hook and the draft of the chain.
    Drawbar Design

    Tech School


    Mr. Richwine,
    Can anyone attend the tech school or do you have to be one of the "Click" to attend??


    The school is open for anyone to set in on but, in order to take the test and become a NTPA licensed official you must be endorsed by either a NTPA member state or by the NTPA itself.

    New SF turbo 3"charger


    Mr. Richwine,

    I hear that Hart has a new 3" charger that measures a fuzz over 3 inches.It was allowed to run last weekend in NC at a non NTPA event. Will that be allowed to run at a UPOC event? If so what's the limit?


    I heard about the new turbo and have had a couple of calls already. I can assure you that NTPA won't allow that and if they are found to be on a tractor at a NTPA event, they won't be allowed to run or if they are found to have run after the fact the tractor will be DQ'd.As luck would have it, I will be at Pinetops and Benson and will make sure the SF chargers are checked.

    Mounting OEM Rollcage


    Hey Richwine,
    I’m new to NTPA and I can’t find the rollcage mounting spec anywhere in the rulebook. I have a D-21 and need to mount an AccuFeed cage to it. Where is it and what do I need to do?


    The Rollcage spec is a SFI 47.1, that’s all that’s listed in the book. The mounting to a OEM chassis is as follows:

    Mounting must use at least 3 axle housing bolts on each side as well as 1 bolt before and after the axle housing. There bolts must be in sheer (horizontal ) with a total of 2 9/16” bolt material. 
    mounting cage

    Rollcage Webbing

    Mr. Richwine,

    I am building a Mini Rod and have a question about the webbing between the upright tubes? Can they be lightened? If so, how much? I have included a photo of the chassis that is available and they look like they have been lightened a lot.

    Yes the shear webbing that goes between the up tubes can be lightened by 40%.
    The Spec says: shear web may have lightening holes but must retain 60% material and must have a minimum of 1 inch around the perimeter of the web on all four sides. This applies to both Mini Rods and Big Tractor rollcages.
    After looking at the photo you are correct this will not pass the SFI / NTPA inspection and will have to be corrected before they are allowed to compete with NTPA.

    Rollcage Inspection Cost


    Mr. Richwine,
    I'm not a member of NTPA but, would like to run at the upcoming event. I need to get my cage inspected, is there a charge for that?

    Here's the program that's been in place since 1999 when the cage was implemented.
    All vehicles that compete at a NTPA event must have the rollcage inspected and display a NTPA/SFI certification sticker or the vehicle will not be allowed to hook.

    1. Upon passing inspection and paying the fee of $75.00 per cage to NTPA on vehicles that have a paid NTPA membership. The rollcage will have a certification sticker applied to it that denotes the inspection date, it will be valid for a period of five (5) years before being required to have their rollcage reinspected. Unless an accident occurs that involves the rollcage.
    2. A service fee of $100.00 will be added to a cage that is on a non NTPA member vehicle. This $100.00 fee will be applied to a regular membership (not per hook) if the vehicle joins NTPA within a 60 day period from the date of inspection.

Contact Info

National Tractor Pullers Association
6155-B Huntley Road,
Columbus, OH 43229

PHONE: (614) 436-1761

FAX: (614) 436-0964